textproduct: Rapid City

KEY MESSAGES

- Warming trend as we move towards and through the weekend.

- Active northwest flow will bring chances for showers and thunderstorms today, and again on Saturday; severe weather is generally not expected at this time.

- Much warmer next week with increasing fire weather concerns due to increased winds and lower relative humidities.

UPDATE

Issued at 942 PM MDT Wed May 6 2026

Minor changes to the previous forecast. Storm track has shifted south some in forecast models for both Thur and Sat impulses. This has resulted in a SW shift in the higher pops, most noticeable in western SD. Dropped highs a couple degrees Thur and esp Fri as the cool front moves through faster. Still on track for a sig warm up next week with 80s and few 90s possible early next week. All else on track.

DISCUSSION

(This Evening Through Wednesday) Issued at 1213 PM MDT Wed May 6 2026

Current Water Vapor and upper air models show northwest flow over the FA, as weak troughing sits over the Great Lakes region and upper ridge builds over the far western CONUS. 18Z Surface analysis has high pressure centered over eastern Wyoming this afternoon. Satellite shows some low-top CU development over the forecast area. Temperatures currently sit in the 40s and low 50s over the region, with winds out of the northwest.

Upper ridge builds over the Rockies tonight and Thursday, resulting in warmer temperatures for the area. Highs Thursday will be in the upper 50s and 60s, while Friday will see widespread 70s. Main concern for Thursday will be the potential for showers/storms as a shortwave rides the northwest flow through the CWA. The better forcing region for precipitation potential looks to be from northeastern WY into the Black Hills and southwestern SD. Low CAPE values (200-400 j/Kg) and some low eff shear will be enough to spark some thunderstorms in the showery regions. Given the forecast thermal profiles, not expecting any severe storm potential, but some gusty winds 40-50mph may be possible near showers/storms.

Dry conditions return Friday, but precipitation chances return Saturday as a weak wave moves thorugh WY into SD/NE. Upper ridge slides over the Rockies into the northern and central plains early next week, resulting in continued warmer temperatures and mostly dry conditions Sunday through middle of next week.

AVIATION

(For the 18Z TAFS Through 18Z Friday) Issued At 1213 PM MDT Thu May 7 2026

Scattered rain showers and isolated t-storms are still expected to cross the region today, starting in northeastern Wyoming. Based on the latest guidance, confidence in shower activity is increasing for KGCC, and have thus added predominant -SHRA while refining the timing on the PROB30 for -TSRA.

Brief periods of MVFR cigs/vsbys will be possible under heavier showers and storms today, especially across northeastern Wyoming, the Black Hills, and far southwestern South Dakota, in an otherwise solidly VFR environment throughout the TAF period. A few storms may produce small hail and erratic wind gusts of 35-40kts.

Further east...confidence in coverage of showers/storms remains lower at KRAP and have continued a PROB30 with refined timing. Precip chances decrease quickly north and east of KRAP into the South Dakota plains.

UNR WATCHES/WARNINGS/ADVISORIES

SD...None. WY...None.